With mark and space adjustment this circuit was found in November 1984 Radio Electronics. The base frequency depends on C1.
We found this circuit in a 1973 publication. The circuit lets frequencies below 480 kHz pass...
This power supply was originally indicated for work with electroplating. The transformer is 2 A or...
This simple circuit serves to identify the terminals of a PNP transistor. For NPN transistors, just invert...